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H Ishida

Publications and source records attributed to H Ishida.

At least 145 records · Page 8Linked to original sources

Effects of physical training and mental practice of in-clothes swimming: assessment by physiological parameters.

PURPOSE: This study examined whether a short-term physical or mental training reduces the physiological load and perceived exertion of the in-clothes swimming. METHODS: The study included 24 male inter-collegiate competitive swimmers with no previous experience of the in-clothes swimming. Prior to the training, the subjects performed 200-meter swimming with two styles of swimming, namely the crawl and elementary backstroke, and the degree of perceived exertion in the Borg scale, heart rate, and blood lactic acid level were determined. Following this baseline determination, the subjects were divided into 4 groups with 6 individuals each. These four groups were Group A "in-clothes training", Group B "image training", Group C "swimsuit training", and Group N "no training". Group A and C were lectured on the in-clothes swimming and practiced 7.5 min-long in-clothes swimming per day for a week with the two swimming styles, with Group A subjects wearing daily clothes and Group C subjects in swimsuits. Group B received 15 min of nonphysical mental practice primarily through viewing video recording of swimming performance everyday for a week. No training was given to Group N. At the completion of the training session, the subjects underwent the 2nd 200-meter swimming, and the physiological parameters were determined. RESULTS: The 1st in-clothes swimming load test showed that the elementary backstroke swimming resulted in significantly lower values of heart rate, blood lactic acid level, and perceived exertion than the crawl. For Group N, no difference was observed in the physiological parameters between the 1st and 2nd load test with either the elementary backstroke or crawl. Upon the 2nd in-clothes load test with the elementary backstroke, all three parameters were lower for Group A, B, and C than those seen for the 1st load test, and these differences were statistically significant, except for blood lactic acid in Group A. The 2nd in-clothes load test with the crawl showed that both heart rate and blood lactic acid were lower than those of the 1st load test for all three groups, with the differences in heart rate and blood lactic acid in Group A and that in blood lactic acid in Group B reaching the statistic significance. With respect to perceived exertion, the Borg score determined after the in-clothes load test with the crawl was significantly reduced for Group A, B, and C. The score after the in-clothes load test with the elementary backstroke was significantly reduced only for Group A. CONCLUSION: The elementary backstroke, when practiced in-clothes, imposes a relatively less physiological load. The present training methods can reduce physiological load and/or perceived exertion of the in-clothes swimming. Thus, both image training and swimsuit swimming are equally effective as a training method of the in-clothes swimming.

Adult↗

Solution structures of the N-terminal domain of yeast calmodulin: Ca2+-dependent conformational change and its functional implication.

We have determined solution structures of the N-terminal half domain (N-domain) of yeast calmodulin (YCM0-N, residues 1-77) in the apo and Ca(2+)-saturated forms by NMR spectroscopy. The Ca(2+)-binding sites of YCM0-N consist of a pair of helix-loop-helix motifs (EF-hands), in which the loops are linked by a short beta-sheet. The binding of two Ca(2+) causes large rearrangement of the four alpha-helices and exposes the hydrophobic surface as observed for vertebrate calmodulin (CaM). Within the observed overall conformational similarity in the peptide backbone, several significant conformational differences were observed between the two proteins, which originated from the 38% disagreement in amino acid sequences. The beta-sheet in apo YCM0-N is strongly twisted compared with that in the N-domain of CaM, while it turns to the normal more stable conformation on Ca(2+) binding. YCM0-N shows higher cooperativity in Ca(2+) binding than the N-domain of CaM, and the observed conformational change of the beta-sheet is a possible cause of the highly cooperative Ca(2+) binding. The hydrophobic surface on Ca(2+)-saturated YCM0-N appears less flexible due to the replacements of Met51, Met71, and Val55 in the hydrophobic surface of CaM with Leu51, Leu71, and Ile55, which is thought to be one of reasons for the poor activation of target enzymes by yeast CaM.

Amino Acid Sequence↗

Calmodulin kinases II and IV and calcineurin are involved in leukemia inhibitory factor-induced cardiac hypertrophy in rats.

We recently reported that leukemia inhibitory factor (LIF) enhances Ca(2+)](i) through an increase in L-type Ca(2+) current (I(Ca,L)) in adult cardiomyocytes. The aim of this study was to investigate whether LIF activates Ca(2+)-dependent signaling molecules, such as calcineurin and calmodulin kinases II and IV (CaMKII and CaMKIV), and, if so, whether these Ca(2+)-mediated signaling events contribute to LIF-mediated cardiac hypertrophy. We first confirmed that LIF increased I(Ca,L) and [Ca(2+)](i) in primary cultured rat neonatal cardiomyocytes. Calcineurin, CaMKII, and CaMKIV activities increased at 2 minutes and peaked by 1.6-, 2.2-, and 2.2-fold, respectively, at 15 minutes. Nicardipine or verapamil fully inhibited these activities. Autophosphorylation of CaMKII was also observed to parallel the timing of CaMKII activity, and this phosphorylation was blocked by nicardipine, verapamil, or EGTA. LIF treatment led to a 3-fold increase in nuclear factor of activated T cell-luciferase activity. To confirm that inositol triphosphate (IP(3))-induced Ca(2+) release from sarcoplasmic reticulum was not involved in this process, IP(3) content and phosphorylation of phospholipase Cgamma were investigated. LIF did not increase IP(3) content or phosphorylate phospholipase Cgamma. KN62 (an inhibitor of CaMKII and CaMKIV) attenuated c-fos, brain natriuretic peptide, alpha-skeletal actin, and atrial natriuretic peptide expression. KN62 suppressed the LIF-induced increase in [(3)H]phenylalanine uptake and cell size. Cyclosporin A and FK506 slightly attenuated brain natriuretic peptide but did not affect c-fos or atrial natriuretic peptide expression. Cyclosporin A significantly reduced the LIF-induced increase in [(3)H]phenylalanine uptake. These findings indicated that LIF activated CaMKII, CaMKIV, and calcineurin through an increase in I:(Ca,L) and [Ca(2+)](i) and that CaMKII, CaMKIV, and calcineurin are critically involved in LIF-induced cardiac hypertrophy.

Aniline Compounds↗

Suppression of pulmonary metastasis using adenovirally motility related protein-1 (MRP-1/CD9) gene delivery.

Previously we showed that MRP-1/CD9 might prevent tumor metastasis by suppression of cell motility and invasion of tissue barriers. The present study explored the possibility of preventing metastasis of mouse melanoma BL6 by expression of MRP-1/CD9 through gene transfer. A replication-deficient adenovirus vector was used for the in vivo transfer of MRP-1/CD9 cDNA. Intratumor injection of an adenovirus vector (rAd-MRP-1/CD9) expressing MRP-1/CD9 resulted in a 73.7% reduction in the number of pulmonary metastases of mice and the median survival time of mice treated with rAd-MRP-1/CD9 was significantly longer than those treated with the rAd-beta-gal vector (103.2 approximately plus;8.5 days vs 71.2 approximately plus;5.2 days, P<0.001 respectively). These results support the expression of MRP-1/CD9 through gene transfer as a therapeutic strategy for preventing metastases and prolonging survival, and support the feasibility of gene transfer in a clinically relevant setting.

Adenoviridae↗

Stereocontrol in rare earth metal triflate-catalyzed 1,3-dipolar cycloaddition reaction of 2-benzopyrylium-4-olate with aldehydes

Exo-cycloadduct was obtained with high stereoselectivity by the addition of ytterbium triflate (Yb(OTf)(3)) (10 mol %) in the rhodium(II) acetate (Rh(2)(OAc)(4))-catalyzed decomposition of o-(methoxycarbonyl)-alpha-diazoacetophenone in the presence of benzaldehyde. In the reaction in the absence of Yb(OTf)(3), almost no selectivity was obtained. Stereoselectivity in the reactions with p-nitrobenzaldehyde, p-anisaldehyde, and benzyloxyacetaldehyde could be also controlled to high exo preference by the addition of Yb(OTf)(3).

Journal Article↗

Systematic synthesis of sulfated sialyl-alpha-(2 --> 3)-neolactotetraose derivatives and their acceptor specificity for an alpha-(1 --> 3)-fucosyltransferase (Fuc-TVII) involved in the biosynthesis of L-selectin ligand.

Sulfated sialyl-alpha-(2 --> 3)-neolactotetraose (IV3NeuAcnLcOse4) derivatives at C-6 of GlcNAc (6-O-sulfo), terminal Gal (6'-O-sulfo), and both GlcNAc and Gal (6,6'-di-O-sulfo) residues have systematically been synthesized. (Methyl 5-acetamido-4,7,8,9- tetra-O-acetyl-3,5-dideoxy-D-glycero-alpha-D-galacto-2-nonulopyranosy lonate)-(2 --> 3)-2,4-di-O-benzoyl-6-O-levulinoyl-D-galactopyranosyl trichloroacetimidate was coupled with 2-(trimethylsilyl)ethyl (2-acetamido-2-deoxy- 3-O-benzyl-6-O-p-methoxyphenyl-beta-D-glucopyranosyl)-(1 --> 3)-(2,4,6-tri-O-benzyl-beta-D-galactopyranosyl)-(1 --> 4)-2,3,6-tri-O-benzyl-beta-D-glucopyranoside to give the suitably protected pentasaccharide which, upon selective removal of the p-methoxyphenyl and/or levulinoyl groups at C-6 of the GlcNAc and the terminal Gal residues, successive O-sulfation(s) and deprotection, afforded the desired three sulfated IV3NeuAcnLcOse4 derivatives. Acceptor specificity of the synthetic IV3NeuAcnLcOse4 probes for a human alpha-(1 --> 3)-fucosyltransferase (Fuc-TVII) was examined to study the biosynthetic pathway of L-selectin ligand. Only the 6-sulfated derivative at C-6 of GlcNAc was recognized by Fuc-TVII to give 6-O-sulfo sialyl LeX.

Binding, Competitive↗

Decreased protein kinase C-epsilon expression in hypertrophied cardiac ventricles induced by triiodothyronine treatment in the rat.

To examine the effect of thyroid hormone-induced cardiac hypertrophy on PKC expression, changes in the expression of PKC isoforms were studied in hypertrophied cardiac ventricles induced by triiodothyronine (T3) injection in the rat. Injection with T3 for 8 days induced 49% increase in cardiac weight compared to controls. Immunoblot analysis of cardiac ventricular extracts showed the expression of PKC-delta, -epsilon, and -zeta in both control and T3-treated groups. The expression of PKC-epsilon decreased by 40% in hyperthyroid rat cardiac ventricles, while PKC-delta and -zeta expressions were barely affected. PKC-epsilon immunoreactivity decreased in both cytosol and membrane fractions. On the contrary, PKC-epsilon expression did not decrease in the extract of hypertrophied cardiac ventricles produced by aortic banding or aortocaval shunt. These results indicate that thyroid hormone down regulates PKC-epsilon expression in the hyperthyroid-mediated cardiac hypertrophy.

Animals↗

Anti-AB titer changes in patients with ABO incompatibility after living related kidney transplantations: survey of 101 cases to determine whether splenectomies are necessary for successful transplantation.

BACKGROUND: A shortage of organ donors for transplantation has become a serious problem throughout the world. To overcome this problem, transplantations across ABO blood barriers have been performed with some success. In general, however, the graft survival rate for transplantation with ABO incompatibility is lower than that of transplantation with ABO compatibility. Unfortunately, the mechanism by which isohemagglutinins might injure an ABO-incompatible graft remains uncertain. Here, the pre- and posttransplantation anti-AB titers in patients who received transplants from ABO-incompatible living donors are reviewed and the pathological findings are compared. METHODS: One hundred and one patients underwent ABO-incompatible living related kidney transplantation (i-LKT) between January 1989 and October 1999 at our hospital. Plasmapheresis and immunoadsorption were performed in all of the i-LKT patients before the transplantation to remove anti-AB antibodies. A splenectomy was also performed during the operation, followed by the local irradiation of the graft with a dose of 150 rad. The anti-AB titers and pathological findings for 93 i-LKT patients, excluding 8 patients who died, were then examined. RESULTS: Immediately after the i-LKT, the anti-AB titer dropped rapidly to below 1:4 in all 93 cases. Seventy of patients (70/93, 75%) showed no elevation in their anti-AB titer during their follow-up. However, the remaining 23 patients (23/93, 25%) showed a significant elevation of their anti-AB titer to over 1:16. Sixteen of these patients (16/93, 17%) exhibited an anti-AB titer of over 1:32. Out of these 16 patients, 11 patients (11/16, 69%) lost their grafts. The anti-AB titer in the remaining five patients (5/16, 31%) spontaneously decreased without any special treatment. Seven patients (7/93, 8%) exhibited an elevated titer of 1:16. Out of these patients, only one patient (1/7, 14%) lost his graft. The elevated titers in the remaining six patients (6/7, 86%) eventually decreased. The graft function improved in patients whose elevated anti-AB titers eventually decreased. Control patients (ABO-compatible kidney transplant patients) showed a normal elevation of their titer values compared with preoperative titers. Pathological findings showed severe humoral rejections in all cases with high anti-AB titers that lost grafts. Humoral rejection was also detected in most of the patients whose anti-AB titer was elevated to over 1:16 after the transplantation, but excellent renal function was resumed once the titers decreased to below 1:4. CONCLUSIONS: In 23 out of 93 i-LKT patients (25%), the anti-AB titers were significantly elevated after the splenectomy. In view of other reports of i-LKT without splenectomy, we feel that a splenectomy in i-LKT patients might be unnecessary. Pathological evidence suggests that the decrease in the anti-AB titer after transplantation might be the net result of plasmapheresis before the operation and the adsorption of antibodies to the endothelium of the transplanted organ after the operation, neither of which is influenced by a splenectomy.

ABO Blood-Group System↗

Analysis of the mechanism of discrepant nuclear morphometric results comparing preoperative biopsy and prostatectomy specimens.

OBJECTIVES: To explore the mechanism for the differing nuclear morphometric results between needle biopsy and surgical specimens of the prostate. METHODS: In experiment 1, a comparison of mean nuclear area (MNA), volume-weighted mean nuclear volume (MNV), and form factor (FF) for prostatic epithelial cells was performed between preoperative needle biopsy and prostatectomy specimens from 5 patients with benign prostatic hyperplasia (BPH). In experiment 2, a scheduled, sequential ex vivo needle sampling from the enucleated prostates (at 0, 2, 6, and 24 hours after surgical resection) was also performed for 7 patients with BPH. The prostatectomy specimens were left unfixed for 2 hours until the second needle sampling was done. Nuclear morphometric parameters were measured on the needle-sampled as well as on the prostatectomy specimens. RESULTS: MNA, MNV, and FF of BPH cells measured on preoperative biopsy specimens were smaller than those of surgical specimens in all 5 of the cases. The results of nuclear morphometry on the materials obtained by ex vivo needle sampling of prostates before and during fixation revealed that the MNA, MNV, and FF for BPH cells of 0-hour specimens were significantly smaller than those for needle samples at 2, 6, and 24 hours after surgical resection as well as those for prostatectomy specimens. CONCLUSIONS: The present study provided further evidence that the ischemic damage caused by delayed fixation could result in a substantial change of the nuclear morphology of prostate cells. An immediate start, as well as a rapid completion, of the fixation procedure seems critical for an accurate nuclear morphometry of prostatectomy specimens.

Biopsy, Needle↗

Acid-promoted rearrangement of carbonate functionality anchored to the lower rim of a Calix

A unique calix[4]arene lower-rim intramolecular rearrangement, resulting in molecular asymmetry arising from the upper- and lower-rim substitution pattern, produces a new class of inherently chiral calix[4]arenes in a partial cone conformation. This was aided by molecular rigidification arising from pi-pi and C-H.pi interactions between bulky lower-rim substituents, with the corresponding circular dichroism spectra exhibiting the most intense bisignate Cotton effects yet observed for calix[4]arenes not bearing a chiral center.

Journal Article↗

Persistent increase in the amount of aquaporin-5 in the apical plasma membrane of rat parotid acinar cells induced by a muscarinic agonist SNI-2011.

SNI-2011 induces the long-lasting increase in the amount of aquaporin-5 (AQP5) in apical plasma membranes (APMs) of rat parotid acini in a concentration-dependent manner. This induction was inhibited by p-F-HHSiD, U73122, TMB-8, or dantrolene but not by bisindolmaleimide or H-7, indicating that SNI-2011 acting at M(3) muscarinic receptors induced translocation of AQP5 via [Ca(2+)](i) elevation but not via the activation of protein kinase C. In contrast, acetylcholine induced a transient translocation of AQP5 to APMs. SNI-2011 induces long-lasting oscillations of [Ca(2+)](i) in the presence of extracellular Ca(2+). Thus, SNI-2011 induces a long-lasting translocation of AQP5 to APMs coupled with persistent [Ca(2+)](i) oscillations.

Animals↗

Sialyl Lewis(x) (CD15s) monitoring as a means to select antirejection therapy in patients with rejection after renal transplantation: CD15s monitoring for treatment and diagnosis in patients with acute rejection after renal transplantation.

BACKGROUND: Sialyl Lewis(x) (CD15s), which is known to serve as a ligand for the cell adhesion molecules E-selectin and P-selectin, is expressed on peripheral lymphocytes in renal transplant patients with rejection. In this study, we examined whether CD15s monitoring could differentiate the patients with rejection in whom steroids were effective from those in whom steroids were not effective. METHODS: To investigate CD15s expression on peripheral lymphocytes, flow cytometry was performed before and after steroid pulse therapy in 20 recipients with rejection after renal transplantation, including 5 recipients resistant to steroid therapy. We also compared CD15s expression with pathological findings before and after steroid pulse therapy. RESULTS: CD15s expression was stronger before steroid pulse therapy in the 5 patients resistant to steroids than in the 15 patients responsive to steroid treatment. In addition, CD15s expression remained high without any pathological improvement in the 5 patients resistant to steroids after steroid treatment, although CD15s recovered to normal levels with remarkable improvement of pathological findings in the other 15 patients. Five patients in whom steroids were not effective, had full recovery of serum creatinine levels as well as CD15s expression after muromonab (OKT3) therapy. CONCLUSIONS: CD15s monitoring might help clinicians to select antirejection therapy.

Adult↗

Ethylammonium and diethylammonium salts of chloranilic acid.

In the crystals of two title salts of chloranilic acid (2,5-dichloro-3,6-dihydroxy-p-benzoquinone), namely ethylammonium chloranilate, C(2)H(8)N(+).C(6)HCl(2)O(4)(-), (I), and diethylammonium chloranilate, C(4)H(12)N(+).C(6)HCl(2)O(4)(-), (II), the chloranilate ions are present as a hydrogen-bonded dimer which has an inversion center. The ethylammonium and diethylammonium ions link the dimers through N-H.O hydrogen bonds, forming a three-dimensional hydrogen-bond network in (I) and a one-dimensional chain in (II).

Journal Article↗

Expression of sialyl 6-sulfo Lewis X is inversely correlated with conventional sialyl Lewis X expression in human colorectal cancer.

Sialyl 6-sulfo Lewis X determinant has been described recently as a major ligand for L-selectin on high endothelial venules of human peripheral lymph nodes. From our investigation of its distribution in human colorectal cancer tissues and cultured colon cancer cells, the sialyl 6-sulfo Lewis X determinant was preferentially expressed in the nonmalignant colonic epithelia rather than cancer cells (P < 0.001; n = 23). This was in contrast to the distribution of conventional sialyl Lewis X, which was preferentially expressed in cancer tissues rather than nonmalignant epithelia (P = 0.007; n = 23), indicating that 6-sulfation predominantly occurs in nonmalignant tissues and is suppressed upon malignant transformation. In confirmation of this, a nonsialylated determinant 6-sulfo Lewis X was also found to be preferentially localized in the nonmalignant epithelia. Significant expression of sialyl 6-sulfo Lewis X was observed in only 2 lines, whereas 8 were positive for conventional sialyl Lewis X, among 13 cultured colon cancer cell lines. Transfection of cells with fucosyltransferase (Fuc-T) VI induced expression of sialyl 6-sulfo Lewis X, whereas transfection of Fuc-T III did not, suggesting that the determinant was synthesized mainly by Fuc-T VI in colonic epithelia. Members of the sialic acid cyclase pathway, the de-N-acetyl sialyl 6-sulfo Lewis X and cyclic sialyl 6-sulfo Lewis X determinants, were also preferentially expressed in the nonmalignant epithelia rather than colonic cancer cells (P < 0.001; n = 23). Stimulation of the sialyl 6-sulfo Lewis X-positive colon cancer cell line with a calcium ionophore ionomycin markedly reduced sialyl 6-sulfo Lewis X and induced cyclic sialyl 6-sulfo Lewis X expression. These results suggested that the metabolic conversion of sialyl 6-sulfo Lewis X into cyclic sialyl 6-sulfo Lewis X by a calcium-dependent enzyme, sialic acid cyclase, as we hypothesized for human leukocytes previously (C. Mitsuoka et al., Proc. Natl. Acad. Sci. USA, 96: 1597-1602, 1999), also occurs in nonmalignant colonic epithelia.

Colorectal Neoplasms↗

Novel synthetic routes to several new, differentially substituted ruthenium tris(4,4 disubstituted-2,2-bipyridine) complexes.

The stepwise synthesis of several novel Ru(tris(pp)) complexes (pp = 4,4'-disubstituted-2,2'-bipyridine; substituent = H, Me, chiral ester, or chiral amide) is described, where the pp ligands may be the same, or different, in each complex. All of the complexes detailed have been resolved into their pure delta- and lambda-enantiomers or diastereomers. The complexes, which are prepared starting from RuCl3, contain novel ligand architectures, with a range of chiral esters and amides attached to the 4,4'-positions of the bpy ligands. It was postulated that these chiral groups would be capable of inducing chirality at the metal center, but our investigations have shown this not to be the case, and in all reactions completely racemic products were formed. Resolution by chiral HPLC, and the subsequent characterization of the products through NMR, UV-vis, and circular dichroism (CD) spectroscopy, has been carried out; the characteristics of the CD spectra have been discussed with respect to the electron-donating/ withdrawing ability of the groups at the 4,4'-positions. The X-ray crystal structure of the optically pure complex lambda-[Ru(dmbpy)2(4,4'-bis((R)-(+)-alpha-phenylethylamido)-2,2'-bipyridine)] x 2PF6 x 2CHCl3 was obtained and solved using direct methods. This result, in conjunction with the CD spectra, enabled the complete and unambiguous assignment of the stereocenters of all of the novel Ru(tris(bpy)) complexes prepared in this investigation.

Journal Article↗

Diastereoselective preparation and characterization of ruthenium bis(bipyridine) sulfoxide complexes.

A new concept in the synthesis of optically active octahedral ruthenium complexes was realized for the first time when cis- or trans-Ru(bpy)2Cl, (cis- or trans-1) was reacted with either (R)-(+)- or (S)-(-)-methyl p-tolyl sulfoxide (2 or 3); this novel asymmetric synthesis leads to the diastereoselective formation of the ruthenium bis(bipyridine) complex cis-delta-[Ru(bpy)2(2)Cl]Cl (4) (49.6% de) or cis-lambda-[Ru(bpy)2(3)Cl]Cl (5) (48.4% de), respectively. cis- or trans-Ru(dmbpy)2Cl2 (cis- or trans-6) (dmbpy = 4,4'-dimethyl-2,2'-bipyridine) also reacts with 2 or 3, leading to the diastereoselective formation of cis-delta-[Ru(dmbpy)2(2)Cl]Cl (7) (59.5% de) or cis-lambda-[Ru(dmbpy)2(3)Cl]Cl (8) (57.2% de), respectively. The diastereoselectivity of these reactions is governed solely by the chirality of the sulfoxide nucleophile. This represents the first process by which a sigma-bonded ligand occupying only a single coordination site has had such an important influence on the stereochemical outcome of a ruthenium bis(bipyridine) complex formation. These novel complexes were fully characterized by elemental analysis and IR, UV/vis, and 1H, 13C, and 2D NMR spectroscopy. An investigation into the chiroptical properties of these novel ruthenium bis(bipyridine) sulfoxide complexes has been carried out, and circular dichroism spectra are used to assign absolute stereochemistry.

Journal Article↗